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Large Quake Swarm At Iceland's Askja Volcano

ASKJA VOLCANO - ICELAND

A large quake sequence totalling hundreds of tremors is ongoing at Askja volcano since 11/9/2019. The largest quake so far has been a magnitude 3.2 quake. The swarm appears to be on the NE margin of the main caldera in an area that has in the past issued lava flows through fissures. There is no clear answer from the Iceland Meteorological Office or other sources as to whether or not this is magmatic or tectonic in nature.

Blogger Jon Frimann seems to indicate the swarm is tectonic, while VolcanoDiscovery.com seems to suggest this is related to magma dike intrusion. Again, no official source has confirmed any of this.

Screen grab from Iceland Meteorological Office showing current state of swarm at Askja caldera.
Askja caldera has seen dramatically increased seismicity since the eruption of Bardarbunga (Holuhraun fissure) commenced and ended and has had minor seismicity daily since. The last eruption of Askja was a VEI 2 occurring in Oct 1961, however it has proven capable of much, much larger eruptions, with a VEI 5 on New Years of 1875. Any current eruptive cycle would likely be a VEI 2 or 3, depending on the interactions with water/ice and magma supply.
Quake swarms and dike intrusions often amount to no activity on the surface of a volcano, so until the Iceland Met Office chimes in with an official prognosis, anything should be considered speculative at this point, however this is indeed a dramatic rise in activity even from the rise in activity post-Bardarbunga. The Bardarbunga dike intrusion has been theorized by some to have affected or influenced the Askja system, so it's anyone's guess at this point.
An eruption of Askja will not likely threaten any population in Iceland, but as seen with Grimsvotn and Eyjafjallajökull, it could conceivably pose a threat to air travel around Europe.
Keep your eyes on the sequence here: https://en.vedur.is/earthquakes-and-volcanism/earthquakes/vatnajokull/

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